Medical ventilating and aspirating apparatus and methods

ABSTRACT

A ventilating/aspirating apparatus, and related methods, the apparatus comprising a catheter tube for evacuation of lung secretions wherein th distal end portion of the catheter tube is disposed at a substantial angle in respect to the remainder of the catheter tube whereby entry into the left lung of a patient may be predictably and accurately tended to without appreciable trauma to the patient. A removable angle retainer is provided for maintaining the configuration of the distal and portion of the catheter tube during storage, prior to use. Radiopaque indicia, selectively located within the wall of the catheter tube, is provided by which the entry of the distal end portion of the catheter tube into the lungs and particulary the left lung of the medical patient can be insured through accurate mointoring visually or by using available radiological techniques.

This application is a continuation of our copending U.S. patentapplication Ser. No. 24,429, filed Mar. 11, 1987, now U.S. Pat. No.4,834,726.

FIELD OF INVENTION

The present invention relates generally to ventilation and aspiration ofthe lungs of a medical patient and, more particularly, to a novelventilating and aspirating apparatus, and related methods, by which asuction catheter tube thereof can be predictably and accurately placedin either lung of a medical patient for removal of tracheobronchialsecretions.

PRIOR ART

The most relevant, known aspirating/ventilating prior art patents areU.S. Pat. Nos. 3,991,762 and 4,569,344. In each case, an essentiallylinear catheter tube is provided for insertion into and removal ofsecretions from the lungs of a medical patient. Difficulty has beenencountered in placing the catheter tube in the left lung of the patientand in verifying such placement. Often the technique required by theprior art is long term and traumatic for the patient. Clearing ofsecretions from the left lung sometimes does not occur, notwithstandingthe belief of the physician, nurse or technician to the contrary.

The literature also confirms that the left lung is more difficult toenter with a suction catheter tube because of its greater angle ofentry. The literature discloses curved-tip and angled-tip suctioncatheters, use of guide marks, in the form of dots, together withradiopaque liquid for catheter tip placement control of the length ofthe catheter to prevent kinking and avoidance of catheter rotationduring placement.

BRIEF SUMMARY AND OBJECTS OF THE PRESENT INVENTION

In brief summary, the present invention is intended to overcome orsubstantially alleviate the aforementioned limitations of the prior artand comprises a novel ventilating/aspirating apparatus, and relatedmethods, the apparatus comprising a catheter tube, for evacuation oflung secretions, having the non-linear distal end portion to facilitateease and predictability of entry to either lung of a medical patient. Inits presently preferred configuration, the distal end portion isdisposed at a substantial angle in respect to the remainder of thecatheter tube. An angle retainer is provided to maintain the angleduring storage, prior to use. A unique method is provided for creatingthe angle in the wall of the catheter tube. Radiopaque indicia matchingthe configuration of the catheter tube is provided for the catheter tubeby which the entry of the distal end portion of the catheter tube intothe lungs, particularly the left lung, of the patient can be reasonablyinsured when blind placement is undertaken and absolutely assuredthrough accurate monitoring, using existing radiological techniques.

Accordingly, it is a primary object of the present invention to providea novel ventilating and aspirating apparatus, and related methods.

An important object of this invention is the provision of anaspirating/ventilating apparatus comprising a novel catheter tube forfacile entry into either lung of a medical patient.

A further significant object of the present invention is the provisionof an aspirating/ventilating apparatus comprising a novel secretionremoving catheter tube having an angular distal end portion for easy andpredictable entry into the left lung of a medical patient.

A further paramount object of the present invention is the provision ofan aspirating/ventilating apparatus comprising a catheter tube having anangular distal end portion and a retainer for maintaining the shape ofthe distal end portion during storage prior to use.

A further valuable object of the present invention is the provision ofan aspirating/ventilating apparatus comprising a novel secretionremoving catheter tube having radiopaque indicia which matches the shapeof the catheter tube and by which entry of the distal end of thecatheter tube into a selected lung of a medical patient can be insuredvisually and/or through radiological monitoring.

It is another dominant object to provide a novel method for creating anangled-tip in a suction catheter tube.

These and other objects and features of the present invention will beapparent from the detailed description taken with reference to theaccompanying drawings

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective representation of a ventilating/aspiratingapparatus embodying the present invention;

FIG. 2 is a perspective representation of the retainer by which theangle in the distal end portion of the catheter tube is retained duringstorage prior to use;

FIG. 3 is an enlarged perspective representation of the distal endportion of the catheter tube of the ventilating and aspirating apparatusof FIG. 1; and

FIG. 4 is a cross-section taken along lines 4--4 of FIG. 3.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Removing secretions from the tracheobronchial tree is an integral partof the cre given to patients who are intubated and receiving mechanicalor other artificial ventilation. Secretions can be excessive in somerespiratory disorders and constitute a serious threat to the personshaving such respiratory disorders. The presence of an endotracheal tubeis a hindrance to the patient's efforts to clear secretions throughnatural coughing. Suction catheters are used to clear such secretionsfrom the patient's airway.

The aspirating/ventilating apparatus disclosed in U.S. Pat. No.4,569,344 is a device, which among other things, is used to clearsecretions from the lungs of a patient. This device is attached to thepatient's endotracheal tube and is included as part of an overallventilation circuit. The suction catheter is enclosed within a plasticbag to eliminate or minimize contamination thereof. As the patientrequires artificial removal of secretions, the suction catheter isadvanced through a fitting of the ventilating device into the patient'sairway and thence into a lung of the patient. Suction is thereafterapplied to remove the secretions. The other lung may likewise beaspirated. The catheter is subsequently withdrawn into the plastic bag.Secretions are thus drawn into the lumen of the catheter tube andremoved. The present invention is directed toward such suction cathetertubes normally forming part of a ventilating/aspirating apparatus of thetype disclosed in U.S. Pat. No. 4,569,344.

The present invention is intended for accurate placement of anangled-tip suction catheter tube in either lung of a medical patient.

Reference is now made to the drawings wherein like numerals are used todesignate like parts throughout. A presently preferred integratedventilator/aspirating mechanism, generally designated 20, is illustratedin the drawings and embodies the principles of the present invention.

Ventilating/aspirating mechanism 20 is illustrated as being connected toa medical patient at a tracheostomy connector 26 or to an endotrachealtube which is left indwelling for repeated use over a protractedinterval of time. Mechanism 20 comprises a central portion comprising asterile internal aspirating catheter tube 22 having a hollow interiorpassageway 24 (FIG. 4) of sufficient capacity to aspirate secretionsfrom the trachea and bronchus. The aspirating catheter tube 22 is formedof a suitable synthetic resinous material which is yieldable butshape-retaining when in an unstressed condition, such as medical gradetransparent or translucent polyvinyl chloride and further comprises anannular wall essentially of uniform thickness throughout havingtypically small uniform inside and outside diameters. The outsidediameter is selected to comfortably pass through the endotracheal tube,and into either lung of the patient.

The aspirating catheter tube 22 has sufficient strength to preventbuckling, bending and twisting of the catheter tube, which wouldotherwise occlude or tend to occlude the interior passageway of thecatheter tube. In the assembled condition, the tube 22 is surrounded insealed relation by a sterile sack or flexible envelope 28, formed ofsuitable impervious synthetic resinous film material of medical grade,such as polyethylene film in sleeve form.

The flexible envelope 28 is selectively attachable and detachable ateach end, as explained herein, allowing ready manual manipulation of thecatheter tube 22 by gripping action on the part of the user applied tothe exterior of the envelope 28. The catheter tube 22 is controlledsolely by manual manipulation thereof through the envelope.

The flexible envelope 28 is held by an interference fit at the oppositeends thereof by collars 30 and 32, respectively. The interference fitcouplings 30 and 32 together with an aspirating vacuum controlled valve40 and the tracheostomy tube connector 26 are illustrated as being ofknown components. These components are described in substantial detailin U.S. Pat. No. 4,569,344, the contents of which are incorporatedherein by reference for purposes of simplifying this detaileddescription. It should be noted, however, that catheter tube 22 is influid communication with the valve 40, which in turn is in fluidcommunication with a vacuum source 42, such as a conventional hospitalsuction system. In short, when the catheter tube 22 is in theappropriate indwelling position in the lung of a medical patient, thevalve 40 is manually actuated so that the vacuum of source 42 is appliedto the hollow interior 24 of the catheter tube 22 thereby causingundesired secretions from the lung to enter the catheter tube throughthe tip openings 43 and to be removed via the hollow 24 of the cathetertube 22. The openings 43 and the open end of the catheter tube tip, at24, are located to prevent plugging.

The connector 26 is illustrated as being in the form of a cross fitting.The fitting 26 provides an external seal against a loss of air or liquidpressures applied to a lung of a patient but accommodates snug slidabledisplacement of the catheter tube 22 through the fitting 26. The fitting26 comprises first, second, third and fourth port structure 44, 46, 48and 50. Ports 48 and 50 are illustrated as being closed by removablecaps 51. Port structure 44 releasably connects through a fitting 52 tothe distal end of the plastic envelope 28. Port structure 46 isappropriately fitted upon an exposed end of an endotracheal tube in thethroat of the patient, while port structure 48 and 50, respectively,with the caps 51 remOved, connect to the output and exhaust terminals ofa conventional ventilator 54. Thus, the ventilator 54 drives air througheither port 48 or 50, respectively, with the caps 51 removed, connect tothe output and exhaust terminals of a conventional ventilator 54. Thus,the ventilator 54 drives air through either port 48 or 50 into therespiratory system of the patient via port 46 under positive pressureand evacuates gases from the respiratory system of the patient via port46 through the other port 50 or 48 to the ventilator 54.

Connector 26 also comprises a hollow irrigation tube 53 joined to thehousing of connector 26 at hollow fitting 55. During periods of non-use,irrigation tube 53 is closed, at its distal end by a removable tetheredplug 57. The irrigation tube is used to deliver an irrigation solutionto the exterior of the catheter tube 22 to remove secretions therefromduring withdrawal of the catheter lube from the respiratory system of apatient and to remove secretions -rom within the catheter tube aftercomplete withdrawal. The specific structure and exact function of theirrigation tube and related parts are set forth in U.S. Pat. No.4,569,344, to which reference may be made. The present invention, toalleviate or overcome problems involved with prior artventilating/aspirating apparatus, comprises a catheter tube which has anangled distal end portion 60. The angle may be on the order of 30degrees. This facilitates predictable and easy entry of the cathetertube into either lung of a medical patient. Thus the present inventionaccommodates facile entry into the left lung of the distal end portionof the catheter tube in question. The distal end portion 60 of thecatheter tube is illustrated in enlarged fragmentary view in FIG. 3. Thedistal end portion 60 in its relationship with the catheter tube 22defines an elbow, which may comprise an included angle 62 of on theorder of 150 degrees. While this particular angle is not critical, ithas been found to be compatible with easy entry of the distal endportion 60 of the catheter tube 22 into the left lung of a medicalpatient. Apart from the curvature location 64, which may angle thedistal tip of the catheter tube 22 through approximately 30 degrees, theportion of the catheter tube 22 which is proximal of the curvature site64 is illustrated as being linear, as is the distal end portion 60located forward of site 64.

The edge of the tip 66 of the distal end portion 60 of the catheter tube22 is illustrated as being somewhat rounded or beveled. The cathetertube 22 including the distal end portion 60 comprises an elongatedradiopaque strip 68. The radiopaque strip 68 is intentionally located sothat it is within the lane which includes the curvature 64 at the insidediameter 70 thereof. While other locations can be chosen, the describedlocation simulates the shape and identifies the exact location of thedistal end portion 60. This allows the utilization of known radiologicaltechniques during placement of the distal end portion 60 of the cathetertube 22 into a lung of a patient, particularly the left lung to insureproper positioning prior to evacuation, under negative pressure, of thesecretions contained within the lung, as described above. A radiopaqueband 72 may also be an aid to the radiologist, doctor, nurse ortechnician in properly placing the catheter tube 22 within the desiredlung of a patient. Furthermore, even without use of radiologicaltechnique, the elongated radiopaque indicia allows the doctor, nurse orthe like to visually orient the catheter tube for entry into the desiredlung.

It is to be noted that during storage and up to the point in time whenthe apparatus 20 is to be used, particularly where the catheter 22 is tobe used to aspirate secretions from the respiratory system of a patient,an angular retainer, generally designated 80, is removably carriedprimarily within the hollow interior 24 of the catheter tube 22 at thedistal end portion 60. See FIG. 1. The retainer 80, as best shown inFIG. 2, comprises an elongated rod 82. Rod 82 has a straight main solidcylindrical body portion 84, which angularly connects to a straightsolid cylindrical distal end portion 86. Portions 84 and 86 areconnected One to another at an elbow or curvature site 88 defining anincluded angle equal to the angle 62. The retainer 80 is preferablycomprised a shape-retaining synthetic resinous material, such as ABS,formed using existing injection molding techniques. The proximal end ofthe retainer comprises an integral finger engaging cross piece 90 and aloop 92, either or both of which may be used to insert the retainer 80into and remove it from the hollow interior 24 of the distal end portion60 of the catheter tube 22. The outside diameter of rod 82 issubstantially the same as the inside diameter at hollow 24 of thecatheter tube 22 so that a snug fit is obtained. Nevertheless, theretainer 80 can be readily manually displaced into and removed from thehollow interior 24 of the catheter tube 22 at the distal end portion 60,without damage to either the catheter tube 22 or the retainer 80. Boththe catheter tube 22 and the retainer 80 will flex and yieldsufficiently to accommodate removal of the retainer.

It is presently preferred that the distal end portion 60 be formed toprovide the illustrated angle 62 by commencing with a catheter tubewhich is initially entirely linear. Thereafter, the retainer 80 is forcefit into the hollow interior of the distal end of the catheter tube.This forces the distal end 60 of the catheter tube into theconfiguration as illustrated in FIG. 3 counter to the memory of thematerial comprising the catheter tube. However, if nothing more is done,the memory of the polyvinyl chloride or other synthetic resinousmaterial from which the catheter tube 22 is made will cause the distalend 60 of the catheter tube to move from the position illustrated inFIG. 3 toward an entirely linear configuration once the retainer 80 isremoved.

To the contrary, with the retainer 80 in place, the distal end portion60 of the catheter tube 22 is subjected to heat. Preferably a stream ofhot air, until memory forces within the material from which the cathetertube is made are negated at the tip thereof and the angle 62 becomessubstantially permanent, subject to the inherent yieldable nature of thematerial. Accordingly, under non-stress conditions the distal endportion 60 of the catheter tube 22 will tend to remain disposed at angle62. It has been found that a stream of hot air having a temperature ofabout 110 degrees celcius applied over an interval of time of 10 secondsto the distal end portion 60 of polyvinyl chloride catheter tube 22 willproduce he required memory relief and new set in the material at thedistal end portion 60 sufficient to retain the angle 62 under non-stressconditions when the retainer 80 is removed.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentembodiment is, therefore, to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims rather than by the foregoingdescription, and all changes which come within the meaning and range ofequivalency of the claims are therefore to be embraced therein.

What is claimed and desired to be secured by United States LettersPatent is:
 1. An indwelling apparatus by which a medical patient issubject to involuntary respiratory therapy and by which secretions inthe trachea and/or bronchi are evacuated, the apparatus during storageand prior to use comprising:an elongated aspirating catheter tubecomprising a main portion comprising a longitudinal axis having a hollowinterior axial passageway and comprising relatively small inside andoutside diameters, an essentially free distal end portion for manualinsertion into the lungs of a patient and axially disposed suction portmeans disposed at the distal tip of the catheter tube in fluidcommunication with the axial passageway; the free distal end portion ofthe catheter tube immediately proximal of the suction port means beingshaped so that at the time of inception of the apparatus it bears asharp acute angular relationship to the longitudinal axis whereby facileaccurate entry into the left lung of the patient is predictablyaccommodated; retainer means comprising a shaft defining a fixedpredetermined angle substantially the same as the sharp acute angleformed by the distal end portion of the catheter tube removablycoextensively disposed in the distal end of the axial passageway at thetime of inception of the apparatus, the retainer means projectingdistally beyond the suction port means for retaining said sharp acuteangle in the distal end of the catheter tube after inception and duringstorage of the apparatus whereby shaping of the distal end portion ofthe catheter tube immediately prior to use in obviated, the retainermeans further comprising handle means exposed beyond the distal tip ofthe catheter tube by which the fixed angle shaft of the retainer meansis inserted and removed.
 2. An indwelling apparatus according to claim 1wherein the distal end portion of the catheter tube is essentiallystraight, the straight distal end portion joining the remainder of thecatheter tube at an elbow comprising said predetermined sharp angle,when in an unstressed condition.
 3. An indwelling apparatus according toclaim 2 wherein the sharp angle is on the order of 30 degrees in respectto the remainder of the catheter tube, when in an unstressed condition.4. A method of making and storing an aspirating apparatus comprising thesteps of:creating a linear elongated aspirating catheter tube formed asone piece from a suitable synthetic resinous material having a hollowinterior, an essentially free distal end portion for insertion into therespiratory system of a medical patient under the manual control of auser and axially-oriented distal tip suction port means in communicationwith the hollow interior; at inception of the apparatus, providing along term shape-retaining retainer comprising rod means having twosubstantially linear sections integrally joined by an elbow comprising apredetermined sharp fixed acute included angle; at inception of theapparatus and before packaging, assembling the catheter tube and theretainer by inserting the fixed angle rod means of the retainer throughthe axially-oriented distal suction port means and a predetermineddistance into the distal region of the hollow interior of the aspiratingcatheter tube thereby causing only the distal end portion of theaspirating catheter tube to conform to the sharp angular configurationof the rod means counter to the memory forces of the material from whichthe aspirating catheter tube is formed; at inception of the apparatusand before packaging, subjecting the distal end portion of aspiratingcatheter tube to heat of a temperature and for a time sufficient topermanently substantially negate said memory forces; storing theassembled heat treated catheter tube and the long term retainer in theangular assembled condition after inception and during a period ofstorage up to the time insertion of the aspirating catheter tube intothe respiratory system of the medical patient is imminent wherebyshaping of the distal region of the catheter tube immediately prior touse is obviated; removing the rod means from the hollow interior of theaspirating catheter tube at the distal end portion thereof via thesuction port means immediately prior to insertion of the aspiratingcatheter tube into said respiratory system while performing no work onthe distal end region of the aspirating catheter tube, the distal endregion, upon withdrawal of the rod means from the hollow thereof,tending to remain in the sharp angular configuration corresponding tothe fixed angular configuration of the rod means in the absence ofstress imposed thereon to the contrary.